NSF International’s Plumbing Program recently introduced a new geothermal listing for piping products that should ultimately produce cost-effective and environmentally friendly methods to heat and cool buildings.

According to the U.S. Environmental Protection Agency, geothermal systems average 40% greater efficiency than air-source heat pumps, 48% better than natural gas furnaces and 75% better than oil furnaces.

NSF’s new geothermal listing service tests and certifies Polyethylene (PE) and Polypropylene (PP) piping system products that meet the following requirements:

• Final performance of the product, which includes testing to ASTM D3035 or AWWA C901 requirements for short-term burst, pressure testing and environmental stress crack resistance;
• Physical properties of the material used in production, including density, flexural modulus, tensile strength, and a PENT of at least 192 hours as required by the Plastics Pipe Institute (PPI) Part Q;
• Long-term hydrostatic stress test, including the evaluation of materials to the requirements of the PPI’s Technical Report 3 (PPI TR-3) as well as testing to European and Asian temperature and pressure requirements; and
• Health effects testing to ensure compliance with Section 4 of NSF/ANSI Standard 61: Drinking Water System Components -- Health Effects if products are to be used in potable water applications.

“This new certification solution provides pipe manufacturers added value and credibility behind the products that bear the NSF-geothermal mark,” said Nasrin Kashefi, general manager, NSF Plumbing Programs. “By having the NSF-geothermal mark prominently displayed on products, manufacturers can demonstrate their commitment to the environment, while reassuring consumers that all testing requirements have been met.”

For meeting all testing requirements, Centennial Plastics PE piping now bears the "NSF-geothermal" certification mark. Centennial Plastics is also certified by NSF for fulfilling the requirements specified in the Uniform Plumbing Code and additional requirements, specified in NSF/ANSI Standard 14: Plastics Piping System Components and Related Materials for use with potable drinking water and NSF/ANSI Standard 61 for health effects.